Limit-gage



'F. O. HOAGLAND.

LIMIT GAGE.

APPLICATION FILED APR. 23. 1918.

Patented July 29, 1919.

UNITED STATES PATENT OFFICE.

FRANK O. HOAGLAND, 0F HARTFORD, CONNECTICUT, ASSIGNOR NEW YORK, N. Y.-, A CORPORATION OF NEW JERSEY. j

. COMPANY, or

LIMIT-GAGE.

TO PRATT & WHITNEY Patented July 29,1919.

- Application filed April 23, 1918. Serial No. 230,234.

To all whom/it may concern:

Be it known that I, FRANK O. HoAcLAno, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Limit- Gages, of whichthe following is a specification. Y

The principal object of the invention is to provide a limit gage'having one 0 its maximum-distance contacts in the form of a cam so constructed that it can be readily moved out of normal position and used to measure the 'amountby which the piece being gaged exceeds the maximum permissible size. A further object of the invention is to provide certain improved detailed features whereby I obtain a construction which is simple and compact'and which reduces the possibility oferror to a minimum. objects of the invention will be apparent from the following specification and claims.

In the accompanying drawing I have shown the embodiment of the invention which I now prefer, but it will be understood that changes may take place within the scope of the appended claims without departing from the spirit of the'invention.

Of the drawing: 7 I 1 Figure 1 is aside view of'a gage embodying the invention.

Fig. 2 is:an end' view.

Fig. 3 is a bottom view. 7

Fig. 4 is a fragmentary enlarged sectional view taken along the lines ff-k of Fig. 2 and Fig. '3. I v

ig, 5 -is a fragmentary sectional view taken along the line 5- 5 of Fig. 4.

Fig.6 is a detailed view of the measuring cam showing the side opposite to that shown in Fig. 4. r I

Fig. 7 is an edge view of the measuring cam. In the drawing I have shown a gage which is in many respects similar tothat shown in my copending application for limitgages, Serial No. 212,596,1iled January 19th,.1918. My present invention is particularly applicable'to a gageof this type but so far as certain features of the invention are con cerned, it is applicable to a gageofa dif ferent type.

As illustrated, 1 represents the main body of the. gage which is constructed from a metallic tube. Thetube is bent into a means of a flat plate Other 'press againstfandfit the cylindrical U shaped form, as shown, and is flattened at. opposite sides to form fiat walls 2 and 3. Except at the ends, the metal of the tube extends inuniform semi-circular curves between the twowalls 2 and 3, thus providing an oval cross section. 1 At the ends the tube has straight sections which are parallel and which haveopposed inner flat walls 4 and 5 extending perpendicularly between the walls 2 and 3; The outer wall of each end section of the tube is preferably bent inward to form a recess, as indicated ate.- One end of the tubular body is closed, preferably by I which is held in place in any suitable manner, as for instance by brazing. The" edges of the a plate 7 are rounded to eliminate sharp corners or angles.

Carried by the parallel end sections of the gage is a pair of opposed: measuring contacts 8 and :9 which extend through alined apertures in the inner and outer walls of the end sectionsof the body. As'illu s5 trated most clearly'in Fig. 4, the aperture in the inner wall is smooth and the aperture in the outer wall is slightly larger and is suitably thread Each measuring contact has a main-cylindrical part which closely fits the aperture in the inner wall, and an enlarged" outerithreaded part which fits the threaded aperture in the outer wall. Each contacthas aslot 10 or other means permitting it to-be readily turned. By means of a screw driver fitting the slot the measuring contact can be adjusted to; any desired position. For locking each contact in adjusted position, I provide'ascrew 11 which extendsthrough apertures in the sidewalls fits the larger aperture in the'wall 3 and the smaller threaded end of the screw fits thesmaller threaded aperture in the wall 2. The head of the screw'is provided with a curved annularsurfacewhich is adapted to part'wo'f the corresponding measuring contact. Then When the screw ll'is tightened the measuring contact is locked against movement, Atthe closed; endof the -gagethere is provided a measurifng contact 12' which is similar to the. contact 8 and which; is similarlylield,.beingadapted to be lockedby a screw 11.-' 7 1 To prevent unauthorized adjusti'nent of the. contacts 8,-9 and 12,1, preferably fill f i 110 form to y Y the v general way part or the ia ge manner the 'ist, Whenfh'e at 13, Thissealing Wax is molded to con-- Y outer contour of the an'd'fi't't ifeifoij'e "serves to provide a smooth 'blltl i'fie as wen prevent adjustment. H v

At the open end of the tubular body there is mounted coeperate-wtith' the eontaet le. This cont act is in the form of a cam 14-. The cam is disklike in form and is rotatably mounted on a pivot pin l5fwhich extends throughsuifiabl'e apertures in the walls 2; "and -3. The pivot pin 15 is exactly opposite the measuring contact illustrated most clearly in Fig. -5,- the in 15 has a 'sho ll derglfi@eng'aging one; side of the 14. ;,The other i side of the cam '14: isengagdd by -a Washer :17 "interposed between the -CtIi'lf'ttIlCl the Wall 2. A screw 18 is threaded i n'tofa central aperture in the -pin 15,,the head of thescr'ev'v engaging the outer-surface ef the all 2 holding the pin 15iii-pla ce. v

Themeasuring ontfact l2 isa'dj'ustefd so that when the: cam 14:;is normal-posh tion, as shownin the drawings, thedistance betWee'n J-them is the maXimu-n1 ;permis sible size of the piece to be gafged. Thus a'djusted the contacts lZ'and 14L constitute maximum-distancecontacts. The contaots8 and :9 are relatively adjusted between them isthe minimu-mpermissible size ofthe piece toflbegaged, The'contacts 9 thusg constitu te minimum-distance contacts. With the .parts adjusted in {this I, gage eanbe used in the usual way, 'an'dfthe piece-togbe gaged must go between 'the coiitadt s 12 and lfhloiit must n u -what at the "emi ters san '9. v j a 1 Itfi's frequently desirable forfthe 1naehinfindsuponktrial'that the piece being; machined is 't'oojlargie, to knoiv {just catip mairks; Th"

point 'b' as"indicatecl'hvthe' V grooves h'o'iv much twing it is inorbl-e'r th jt he 'm'ay properlysethistoolr sfan'aa iaon ar, impr ed gage permits to eadilysidtermine'thifs. The eater su fac ofthe me gerlag-cam piral inform, uniformly 'decreasing" in "radius froinj'ftl'ie, lpoint ai t f cit-rived: s

"The endpart's' artisan-1&2 aid "3 adjacent {'6 e' measuring (57v marefrounde'd 'or tea eled "and one bfra ref' bly' each offfthem is provided With'fan indicating ar'k '1 surface ofthe cg ufnl'tfis'prov-ide ctr-preferably t 7, face'near the edge as hie-reared at-2o. 'Tfhemark's' @0011 each side at the earner adapted to"eo6per ate with the corresponding mark la-onfthe body WallQfr 'Prefe'ra l .7 v are" radial and are" inane form of 1 small $h DQd QTOOVBS or notches. 'Adjatggmffih' opposite '19" the cam will be a measuring contact adaptedto' .The-b'ush-in g-23 is cut Ea so that the distance oi'vn thi's 'decreafse in radius re stfitable designating" numerals, in

the present "case the numeralsrunning froilii earn isinfzero 0 to 60 at intervals of five. The numerals are so arranged that when the zero markis in pos'iti'on'to indicate maxirnum -permiss'ible distance, asbefore described. As before stated, the d'eerease in radius from the point a to the point (3. the present case is .0601; In this 'safniearcthere are sixty divisions, eachdivision thus representing .001 decrease in radius. If the operator turns the cam to a position such that the gage will pass the piece being measured, the reading on the ham opposite themark I9 will indicate in thousandths-ofan inchthe amount by which the piece-being ineasured is in 'eXcessof thermal:- i'muin permissible size. w

Preferably, to? prevent free pivotal movement of the cam 14, I provide a suitable hold ing mea;ns.- This holding means is preferably inthe form of a de't'ent 21 adapted to engage the marking grooves or notches '20 on one side'of the disl As il'lustrated, this detent is formed as :a: part of a plungqer 22 longitudinally movable ina bushing 23 po- $iti011'edf-in apertures in the Walls '2 and -3. Way atoneside'to permita ecess to the cam, and the pl unger 22 isjrecesse'd adjacent the I detent At the end of t'he plunger opposite the detent is an enlarged head 24 which, --fits' an enlarged pa-rtvo f thebu'shing -Bos-itioned Within the bnshi-ng-andejngaging theh eadis a coil spring25 which servesto press the head out- 7 the detent 21' being forced out or one groove 20 and moving lnto 'anothergroove 20 under theaction of the spring 25'. r Preferably a part ofthe miter-surface,"of the cam from-the1pointa to the'point 0'" is concentric. j It will be obvious thata-ny part off this "coneentric. surfacegjnay be positioned op osite the edema-e12 'ior'iIr-dica't'ing'tl1e 7 maximum. permissible SlZe of the pice beil'ig gaged. As indicated,this'conben trie sectionot :the cam extends over-four divisions, thus presenting xfi've different nornialoi" ,z'erofpositions, theseteing presented by'iive Zero marks, as indicate Any "onejof-th'e five Zero marks '20' "1ay*be placed "opposite the reqrre enciing mark the distahee between'the 'qontact 12 ahd the surface of the 'cam "14; "This" arrangement prevents excessive "WeiL'i" one Zero point. Preferably the {notches which are engaged by the dete 'nt 2livhenthe Without "ifil'ijaiigi'ng position, are deeper than the 7 other notches,

as indicated at These notches have perpendicular sides so that when the detent 21 has enteredv one of them it will positively hold the. cam :lt against movement: Therefore, when the detent is engaged in one of the notches 20*, the gage can be used in the usual manner without any danger of the cam beingmoved so as to give an erroneous reading. When the operator desires to move the cam from the zero position, this can be done by pressing on the head 24 of the plunger 22 and then moving the detent 21 out of engagement with the cann Then the cam canbe turned, the detent being permitted to engage one of the notches 20.," V V lVhatI claim is:

1. A limit gage comprising in combination opposed minimum-distance measuring contacts in normally-fixed relation, to each 7 other andfopposed maximum-distancemeasuring contacts of which one is in'the, form of an adjustable spiral cam, the distance between the last said contacts having a normally fixed minimum value slightlygreater than that between contacts.

2. A limit gage comprising in combination opposed minimum-distance measuring contacts in normally fixed relation to each other and opposed maximum-distance measuring contacts of which one is in the form of an adjustable pivotally mounted spiral cam having surface markings to indicate the changes in distance resulting from its adjustment, the distance between the last said contacts having a normally fixed minimum value.

3. A limit gage comprising in combination opposed minimum-distance measuring contacts in normally fixed relation to each other and opposed maximum-distance measuring contacts of which one is in the form of an adjustable pivotally mounted spiral cam, the distance between the last said contacts having a normally fixed minimum value, and means engaging the cam to prevent free pivotal movement thereof.

l. A limit gage comprising in combination opposed minimum-distance measuring contacts in normally fixed relation to each 7 other and opposed maximum-distance measuring contacts'of which one is in the form of an adjustable pivotally mounted spiral cam, the distance between the last said contacts having a normally fixed minimum value, and a spring-pressed element'engaging the cam to prevent free pivotal movement thereof.

5. A limit gage comprising in combination opposed minimum-distance measuring 7 7 contacts in normally fixed relation to each other and opposed maximum-distance measuring contacts of which one is in the form of an adjustable pivotally mounted spiral cam the minimum distance andv releasable means said contacts being in able pivotally mounted cam hav ng a spiral a having spaced notches in one of the surfaces thereof, the distance between the last said contacts having a normally fixed minimum value, and a spring pressed detent cooperating with the notches to yieldably holdthe cam in adjusted position.

6. A limit gage comprising in combination opposed minimum-distance measuring contacts in normally fixed relation toqeach other and opposed maximum-distance measuring contacts of which one is in the form of an adjustable pivotally mounted spiral cam having spaced notches in one of the side surfaces thereof, the distance between the last said'contacts having a normally fixed minimum value, means cooperating With the notches to enable them to, serve as indicating marks, and a spring-pressed detent cooperating with the notches to yieldablyvhold the, cam in adjusted position.

7. A limit gage COIDPI'lSlDg in combinacontacts in normally fixed relation to each other and opposed maximum-distance measuring contacts of which one is in the form of an adjustable pivotally mounted spiral cam, for holding the cam the distance between the last said contacts having a normally fixed minimum value, in

a definite predetermined zero position.

8. A limit gage comprising in combination opposed measuring contacts, one of the said contacts being in the form of an adjustable pivotally mounted spiral cam having spaced notches in one of the surfaces thereof and having a supplemental notch deeper than the others, and a spring-pressed detent cooperating with the notches to yieldably hold the cam in adjusted position and adapted to enter the deeper supplemental notch to positively hold the cam in a definite predetermined zero position.

9. A limit gage comprising in combination opposed measuring contacts, one of the said contacts being in the form of an adj ustable plvotally mounted cam having a con centric peripheral section, and means for holding the-cam with any one of a plurality of parts of the concentric section opposite the companion measuring contact.

10'. A limit gage comprising in combination opposed measuring contacts, one of the said contacts being in the form of an adjustable pivotallyimounted cam'having a concentric peripheral section and having a plura lity of spaced notches in a surface thereof, and a spring-pressed detent adapted to enter any one of the notches to positively hold the cam with any one of a plurality of parts of the concentric section opposite the companion measuring contact. V

11. A limit gage comprising in combination opposed measuring contacts, one of the the form of an adjustperipheral section and a concentric peripheral section and having aplurality of spaced notches in a surface thereof andalso aplura'lity of supplemental deeper :notches Ill'lzthfl said surface, and a spring=pressed detent adapted to cooperate with anyone 'Ofwthfi first said notches to yieldably hold-the cam in adjusted position and adapted :to enter any one of-the supplemental deeper notches to positivelyhold the cam with any oneofa plurality of parts ofthe concentric section opposite the companion -measuri-ng contact.

12. A limit gage comprisingin combination a hollow sheet m'etal body, and opposed measuring contacts, -one of -the said contacts being in the form-0f anradjnstablespira l cam pivotally :mounted between opposite 7 Walls of thebo'dy.

V 13. A limit gage comprising in :ecmbination a hollow sheet In'etal body, opposed minimum-distance contacts carried by the body, and opposedmaximum distancemeasuring contacts carried by tlre body, one of the last said contacts being in the form of an adjustable spiral cam pivotally mounted between opposite Walls .ofsthe body. I a

'14. A limitgage .comprisingvin combination afholloW. sheet metal body, and opposed measuring contacts, being :in the form of an :adjustablegspiral cam having indicating 'marks; on :the 1 v sides thereof and pivotally'mounted between -cop posite'walls of.-thebodythevsaid Walls having-marks 'to cooperate with :the marks on the sides of-"the'ca'm. 1

- l5. Alimitgage comprising in (301111311121? tion-a hollow-sheet metal :body, opposed measuring acontacts,:one of the said contacts being in :the :form of innatdjll'StfiblQSPil'Etl cam pivotally mounted between opposite Walls of the body, and meanslengaging the camiftofipreyent:l reezplmtalazmovementJthereof, the said means CQIHPHSIIL-grfl plunger one-of the'said contacts 7 movable.perpendicularly. to azthe saldz-opposit-e Walls through apertures-therein.

testimony wheneofyl hereuntoaffixmy signature. I V 7 1 I O.;HQAGLAND.;

copies of this patent'may he-icbtaind Flor. 'fiwe cents each, tby'addressing "the V-flcmmissioiier 'o-f fatezits, i Washington, .D. 0."

It is hereby certified that in Letters Patent No. 1,311,349, granted Jus 29, 1919, upon the application of Frank O. Hoagland, of Hartford, Connecticut, for an iniprovement in Limit-Gages, errors appear in the printed specification requiring correction as follows: Page 3, line 91, claim 7, after the Word and comma cam,

insert the clause the distance between the last said contacts having a normally fixed minimum value, same page and claim, comrnencing with the article the, line 93,

as now numbered, strike out all to and through the Word value, line 94; and

that the said Letters Patent should be read with these corrections therein that the.

same may conform to the record of the case in the Patent Office.

Signed and sealed this 30thday of Septernber, A. D., 1919.

[SEAL] M. H. OOULSTON,

Cl. 33143. Acting Commissioner of Patents. 

